Before we get to the results, it might be worth going over what exactly makes a diner. For some readers, any breakfast spot, hotcake house or burger joint with a roadhouse vibe both qualified and represented a crime for not being included.

Yes, we stretched the diner definition for our own list. Still, not all of these reader picks qualified (I'm looking at you, Dea's In & Out).

For reference, here are three elements that most diners share:

Layout: A true diner is as much design as it is menu. Originally built inside pre-fab structures that roughly resembled traincars (and were transported as such), diners typically feature a simple layout, with lunch counters facing a long kitchen. It's a look mimicked on a much larger scale by modern diners, including several chains. If a restaurant doesn't have a lunch counter or booths, if the decor goes for cutesy instead of streamlined, it probably isn't a real diner.

Hours: Similarly, we're of the position that any diner worth its salt should probably be open for dinner, if not 24 hours. If you're only open from 9 a.m. to 3 p.m., you're probably a breakfast or brunch spot. Yes, this severely limits the diner options in Portland, but it also marks another point in favor of chains -- yes, even Denny's -- that made our list.

Menu: Mostly American, with pancakes, eggs and hash browns preferably served all day alongside burgers and club sandwiches. Sometimes, as with the East Coast's Greek-owned diners or Portland's own Korean-American Cameo Cafe, it's the specials that give the restaurant character.

Still, as the Supreme Court might say, we'll know a diner when we see it. In that spirit, here are 15 more diner recommendations from our readers, in alphabetical order.